The research simulates two different types of behavior occurring outside of the laboratory. The first models the sequence of phases involved in feeding in the natural environment: the intent is to simulate the natural ecology of the pigeon. This experiment extends the generality of observations made with other species to pigeons. An experimenter-defined operant response replaces the natural foraging behavior, and completion of the response requirement allows the non-food-deprived pigeon to eat until it terminates the meal. The second experiment uses pigeons to model basic economic behavior in man. Non-food-deprived animals living continuously in the experimental environment will perform an operant response that results in the acquisition of stimuli. The stimuli can be traded for food, with the amount of food available determined by the number of previously earned stimuli. The sequence response--stimulus--food is seen as analogous to the sequence labor--money--commodity in human economics. The procedure meets many of the characteristics of the monetary exchange process in humans, and it thereby can yield rigorous experimental data that could be relevant to an understanding of economic processes. At the same time, the research extends the concept of conditioned reinforcement to the non-deprivation unlimited-access-to-food situation.